Question

I am having trouble with the 2nd question. "Write a formula that expresses y in terms of x." I formula I was able to come with is y=1.1x+4.1. But it keeps saying it's wrong. I even got the last question right using this formula.

Answer 1

9514 1404 393

Answer:

a) 1.1

b) y = 1.1x +4.07

c) 129.47

Explanation:

Your calculation of the slope is correct: m = 1.1

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Your calculation of the y-intercept can be refined:

b = y -mx

b = 6.82 -1.1(2.5) = 6.82 -2.75 = 4.07

Then the equation is ...

y = 1.1x +4.07

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Using x = 114, the value of y is ...

y = 1.1(114) +4.07 = 125.4 +4.07 = 129.47

_____

Additional comment

When decimal numbers are involved, computers often need a bit of tolerance with respect to the exact numbers. Apparently more "slop" is allowed for the number 129.5 than for the number 4.1. As we see, the "exact" values are 129.47 and 4.07, respectively. These cannot be represented exactly as floating point numbers in a binary computer.